Method for verifying optical approximatino correction

Abstract

A method for checking optical proximity correction comprises: providing at least one graph to be exposed through the optical proximity correction; performing the resolution reinforcing and the optical proximity correction to the graph to be exposed, wherein after the optical proximity correction, the graph to be exposed has correcting rims; acquiring first derivatives of lighting intensity focusing distance of each correcting rim of the graph to be exposed, wherein, if the first derivatives of lighting intensity focusing distance of all correcting rims of the graph to be exposed are larger than critical values, so that the correcting rims conform to the condition, the check is over, if the first derivatives of lighting intensity focusing distance of all correcting rims of the graph to be exposed are smaller than critical values, so that the graph to be exposed must be performed with common check until the all correcting rims conform to the requirement. The invention calculates the first derivatives of evaluating point lighting intensity focusing distance of each correcting rim of the graph to be exposed, firstly screens out the graph to be exposed conforming to the requirement, then performs the checking steps to the graph to be exposed under different conditions, and saves the time for checking the optical proximity correction.

Description

technical field [0001] The invention relates to the technical field of semiconductors, in particular to a method for calibrating Optical Proximity Correction (OPC, Optical Proximity Correction). Background technique [0002] Fabrication of integrated circuits on semiconductor substrates typically involves a variety of photolithographic steps. As more and more circuit components are covered on the semiconductor substrate, the feature size of semiconductor devices is also getting smaller and smaller. As the dimensions of the circuit elements approach the wavelength of exposure of the lithographic system, the shape of the resulting circuit element becomes significantly different from the corresponding pattern on the reticle. For example, the line width of a circuit element may change as other lines approach or the end of a line tends to shorten or "pull back." This inconsistent line width or "pull back" may cause otherwise identical circuit elements to appear differently. The...

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Problems solved by technology

[0011] In the above-mentioned correction method, it takes a long time to check the nine conditions consisting of energy and focal length for all the corrected edges of the graphics to be exposed. When the optical proximity correction of some graphics to be exposed has been relatively accurate, then The time it takes to check the 9 conditions on this part of the graphics to be exposed is actually a waste

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